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    <script>
        function maxincome(arr) {
            var max = arr[1] - arr[0];
            for (var i = 0; i < arr.length; i++) {
                for (var j = i+1; j < arr.length; j++) {
                    if (arr[j] - arr[i] > max) {
                        max = arr[j] - arr[i];
                    }
                }
            }
            return max;
        }
        
        console.log(maxincome([7, 1, 5, 3, 6, 4]));
        console.log(maxincome([7, 3, 5, 9, 1, 2]));
    </script>
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